Evaluation of Corrosion Susceptibility of Conventional Dual-Phase Steels Used in the Automotive Industry

Role of Ni Content on Microstructure, Mechanical Property, and In‐Site Local Corrosion Behavior of Welded Joints Produced by Laser Welding of Dual‐Phase Steel

“…Furthermore, owing to the coarse grains [ 53,54 ] and residual stress [ 55 ] of welded joints, pitting corrosion also occurs in welded joints because the residual stress causes Cl − to migrate along the stress gradient easily during the corrosion process. [ 23,56 ] With an increase in the corrosion time (Figure 8c–f), the number of pitting sites gradually decreased, and the overall current density value of the welded joint gradually decreased, owing to the gradual inhibition effect of the corrosion products, Fe(OH) 2 . When the corrosion time was increased to 4 h (Figure 8g,h), the pitting sites almost disappeared.…”

“…[22] Welded joints suffer from corrosion in severe environments, especially in media with substantial salt or areas with acid rain (mainly nitric and sulfuric acids). [23] The control or addition of alloying elements to welded joints or substrate materials also changes the corrosion potential and renders steel susceptible to electrochemical corrosion in corrosive media. [24,25] The corrosion rate of the welded joint decreases from 21 to 2 mm year À1 by adopting metal inert gas brazing instead of metal inert gas welding.…”